Carbocyanines from alicyclicdioxy azoles



Patented Oct. 21, 1947 CARBOCYANINES FROM ALICYGLIODIOXY 'AZOLES Alfred W. 'Anish, Johnson,

N. Y., assignors to General Ani- .Binghamton,

and Lee .0. Hensley,

line & Film Corporation, New York, N. Y., 'a

corporation of Delaware No Drawing. Original application August 16, .1944, Serial No. 549,789. Divided and this application August 16, 1944, Serial No. 549,788

I 8 Claims. 1

The present invention relates to .new compounds of the thio and seleno-carbocyanine type and to a method of preparing the same.

In certain processes of subtractive multi-co'lor photography a multi-layer photographic material is used in which the lowest lightesensitive layer is sensitive only for red above 6000A. U. (in the region of the threshold of sensitivity). This redserisitive layer must always be insensitive to bluegreen light since the presence of blue-green sensitivity gives rise to falsification of color. In all color-photography processes in which the color of the component pictures is produced bycolor development, there maybe-present in the photographic layer in addition to the sen si-tizer a color former which, when the exposed silver halide emulsion is developed, combines with the oxidation product of thedeveloper to form a sparingly soluble dye distributed in the layer proportionately to the quantity of silver image. In this case, a sensitizer must be selected, the effect of which is not enfeebled by the presenceof the dye component. Sensitizers are already known which have a high intensity in the red region of the spectrum but, these for the most part are enfeebled by the presence of a dye component.

It is known that many carbocyanines of which the 5, fi-position of the benzene nucleus is occupied, sensitize photographic silver halide emulsions to high red sensitivity. Most of these carbocyanines, however, are not suitable for sensitizing silver halide emulsions containing-color coupling components. This is thought to be due to a physical displacement which the sensitizing dye undergoes when color coupling components are added. That is, the sensitizer isadsorbed to the surface of the silver halide grain, and then, with addition of color component, is displaced therefrom.

An object of the present invention is to provide a class of sensi-tizers which are free fromthe disadvantages noted above.

A further object is to providea new. class :of thio and seleno-carbocyanines containing a hydrogenated ring system as a part of the cyanine dye molecule.

A further object involves a method of preparing such thio and seleno-carbocyanines.

A still further object is to provide thio and seleno-car'bocyanines which are added to photographic emulsions, or coated thereon as an-overcoating, whereby the sensitivity of the photographic emulsion is increased.

Other objects andadvantages of this invention will become apparent by reference to the following specification in which its preferred details and embodiments are described.

This invention is based on the discovery that thio and 'seleno-carbocyanines containing a cyclic hydrocarbon substituted dioxy ring structure as part of the cyanine dye molecule not'orrly sensitize a photographic silver halide emulsion to high red sensitivity, but are also compatible with color coupling components for the cyan dye image. In the latter combination the sensitizing action of the dyes is not impaired or diminished. In addition to these desirable characteristics, it has been further found that when used in conjunction with color coupling components for the blue-green image, the spectral curves of these dyes show a desirable gap in the green region of the spectrumthat is, the dye sensitivity is more selective to the red spectraliregion. The sensitizing capacityof these dyes is not only maintained in the presence of color formers for the bluegreen image, especially those color formers containing long chain hydroxyalkyl groups, but is increased, and in part rendered more selective. This entirely new property is .most surprisingand wholly unexpected. An additional advantage of these dyes is their ability to remain fixed in the one layer in which they are originally deposited.

The sensitizing dyes suitable for the purpose of the present invention have the general formula:

wherein It represents the methylene groups necessary to complete .at least a 5-membered alicyclic ring system such as cyclopentylidene, cyclohexylidene, cycloheptyliden-e, and the "like, R1 and R2 are alkyl groups, e. g., methyl, ethyl, propyl, :butyl, :amyl, etc, Yrepresents sulfur or selenium, X represents an acid radical, e. g., 01,

Br, I, S04, C1104, SO4CH3, SO4C2H5, SO3CsH4CH3 and the like, and Z represents a grouping of atoms necessary to complete a heterocyclic ring usual in the cyanine dye art, such as indolenine, thiahad a boiling point of 125 C. at 12 mm. M. P. 44 C.

The cyclohexylidenedioxybenzene was converted to 1,2-dinitro-4,5-cyclohexylidenedioxybenzole, benzthiazole, benzselenazole and the like; 5 Zone by t eat n the fo mer With a mi tu e of these rings may be substituted by alkyl as above, glacial acetic and fuming nitric acids. The rearyl, e. g., phenyl, naphthyl or anthranyl, sulting product was then converted to the disulalicyclic ring system of the same value as R, fide by treating it in 200 cc. of boiling ethyl a100- alkoxy, e. g., methoxy, ethoxy, propoxy, butoxy, hol with a fused mixture of equivalent quantities etc., alkyldioxy, or cycloalkyl dioxy nuclei. of sodium sulfide nonahydrate and sulfur in small These sensitizing dyes are obtained by conportions until a violet color persisted for a few densing quatenary ammonium salts of thiazoles minutes. The solid was filtered from the cool and selenazoles containing an alicyclic dioxy mixture, washed alternately with water and alring such as cyclopentylidenedioxy, cyclohexylcohol, and dried. idenedioxy, or cycloheptylidenedioxy ring as a e m of e fid Wa a d d to a mi part of the nucleus with ethyl-orthoformate or ture consisting of 28 cc. of acetic anhydride, 22 with Z-(p-acetanilido vinyl) -5, G-methylenedicc. of glac a c acid and 3 cc. of acetyl oxybenzthiazole ethiodide, 2 3- acetanilido chloride, and heated on a steam bath. Eleven vinyl) 5, 6 cyclohexylidenedioxybenzthiazole gms. of zinc dust was then added in small porethiodide, or the corresponding seleno derivations with stirring to the heated mixture. The tives thereof. free base was precipitated from the acid reaction The alicyclicdioxybenzenes used in preparing mixture by pouring into 6 Vo u es f c d Water. the alicyclicdioxybenzthiazoles and alicyclicdi- The 2-1nethy1-5, y y e t oxybenzselenazoles which are condensed with any Z016 w s fi t d d and had a melting point one of the above listed intermediates or coupling 25 0f 'm- The y -pa e agents, are readily prepared by reacting catechol salt was made in the usual manner and had a with a cyclic ketone as described in Recueil melting Point o Travaux Chimiques des Pays Bas, vol. 54, 997 0.69 gm. of th quat na y s t t p p (19%) was treated with 0.5 cc. of ethyl-orthoformate in The following examples describe in detail the 5 gms. of py in the Presence of a tr e o methods for accomplishing the above objects, but tliethylamihe a B for 3 hOuTS- p it is to be understood that they are inserted merecooling. 20 of water was added. After standly for the purpose of illustration, and are not Overnight, the Solid t S p ted s disto be construed as limiting the scope of the in- Solved in 15 o hot -p p a c l a d the vention, solution treated with 3 cc. of 20% potassium Example I iodide solution, filtered and allowed to cool. The 3,3-diethyl-6,6-5,6-dicycloheigggilgiedioxy-benzthiocerbocyanine 0 S crystallized from ethyl alcohol as the iodide. The

HloHlo 40 crystals melted above 250 C. Incorporated in a gelatino silver halide emulsion containing about 4-5% of silver halide, the 0 N dye sensitized to about 6800 A., with a maximum sensitivity at 6400 A. I CH Twenty milligrams of the sensitizing dye pre- 0 s pared as above was dissolved in cc. of methyl E alcohol, and added to one kilogram of silver halide H3C\ /o c: H gelatin 8111111151011 containing about 10% gelatin,

5% of si ver halide and 12.0 gms. of N-octa- CHT'CH 0 N/ decyl-l-hydroxy-2-naphthoylamine. The coated emulsion had a maximum red sensitivity at about Cyclohexylidenedioxybenzene was prepared according to the above publication by dissolving 6650 A., and developed to a blue-green image with p-phenylenediamine developer. The sensitizin dye did not difiuse in multi-layer coatings.

Example II 3,3'-diethyl-5,6'cyclohexylidenedioxy-5,6-methylenedioxy-benzthiocarbocyanine iodide 02115 I CH:

250 milligrams of z-(p-acetanilido vinyl) -5,6- methylenedioxybenzthiazole ethiodide prepared by heating at 135 C. a mixture of equal weight portions of 2-methyl-5,6-methylenedioxybenzthiazole ethiodide and diphenyl formamidine in acetic anhydride for forty minutes were mixed with an equal amount of 2-methyl-5,6-cyclohexylidenedioxybenzthiazole ethyl-p-toluenesulgms. of catechol in gms. of hot anhydrous 65 cyclohexanone and treated with an excess of phosphoric anhydride gms.) After the addition was completed, the stirring was continued for a short time, and the upper layer decanted. The decanted material was mixed with cc. of a dilute solution of sodium carbonate and steamdistilled. The distillate was extracted with ether and the dried solvent evaporated. The residue fonate prepared according to Example I, in 5 cc. of the cyclohexylidenedioxybenzene was distilled of pyridine and 3 drops of triethylamine. The at reduced pressure and the resulting distillate 75 mixture was heated to reflux for 1 hour, cooled,

and an equal volume of water added. The dye phenylenediamine developer. The dye did not crystals which separated out on standing were difiuse in multi-layer coatings. filtered off and recrystallized from ethyl alcohol. When 8.0 gms. of l-hydroxy 2,4-dichloronaph- Incorporated in a gelatino. silver halide emulthalene were substituted for 12.0 gms. of N octasion Containing a out 45% of silver halide, the 5 decyl-l-hydroxy-2-naphthoylamine, the coated dye sensitized to about 6850 A, With a maximum emulsion showed a high red sensitivity, and desensitivity at 6420 A. veloped to a blue-green image with a p-phenyl- Twenty-five milligrams of the sensitizing dye enediamine developer.

Example IV 3,3-Diethyl-5,6-5,6'-dicyclopentylidenedioxy-benzthiocarbocyanine iodide above prepared Was dissolved in 50 cc. of methyl 5.3 gms. of 2-methyl-5,6-cyclopentylidenedialcohol, and added to a kilo of silver halide gelaoxyloenzthiazole ethyl-p-toluenesulfonate, pretin emulsion containing about 10% gelatin, 4-5% pared in a manner similar to the corresponding of silver halide, and 12 gms. of 3,5-di(phenyl- 2 methyl-5,6-cyclohexylidenedioxybenzthiazole amino) phenol. The coated emulsion showed a in Example I, and five gms. of ethyl-orthoformhigh red sensitivity, and developed to a blueate were refluxed in 20.0 cc, of pyridine for 2 green image With a p-phenylenediamine develhours. An equal volume of water was added and Ope the dye which separated was filtered off, washed Example III 3,3-dietl1yl-5,6-cyclohexylidenedioxy-fi,6'-1 1et ylenedioxybenzthiobenzselenocarbocyanine 0.8 gm. of 2-(B-acetam'1ido vinyl) -5,6-cyclowith water, and crystallized from methyl alcohol.

hexylidenedioxybenzthiazole ethiodide and 0.6 gm. Incorporated in a gelatino silver halide emulof 2 -methyl-5,6-methylenedioxybenzselenazoleta g 4-5% of s ilvenha e, t e dye ethyl-p-toluenesulfonate were mixed with 25 cc. Sensltlzed to about 6300 Wlth a maxlmum of pyridine and 0.5 cc. of triethylamine added. sensitivity at 9 The mixture was refluxed for 1 /2 hours. The dye Twenty-five mllhgrams of the Sensltlzmg dye solution was diluted with water and allowed to fi 'i p f h Y' f added 5 of Silver stand overnight. The dye crystals which sepg gfi ifgg g?: ;g; gf arated were filtered off and washed with water, s hydr )xyquirmlme as m 1 formeh J and recrystallized from ethyl alcoholcoated emulsion showed a high red sensitivity,

Incorporated in a gelatino silver halide emuland developed to a b1ue-green image with a sion containing about 4-5% of silver halide, the phenylenediamine developer.

Example V 3,3-Diethyl-5,fi-cyclohexylidenedioxy-6',7-benzobenzthiocarbocyanine iodide 02H; I CgHg dye sensitized to about 6850 A, with a maximum 5.4 gms. of Z-(B-acetanilido vinyl) -5,6- cyclosensitivity at 6450 A. hexylidenedioxybenzthiazole ethiodide was mixed Twenty-five milligrams of the sensitizing dye with 4.0 gms. of 2-methyl-6,7-benzobenzothiaprepared as above was added to a kilo of silver zole ethyl-p-toluenesulfonate, 20.0 cc. pyridine halide gelatin emulsion containing about 10% and 4.0 cc. triethylamine. The mixture was gelatin, 4 5% of silver halide and 12.0 gms. of heated to reflux for one hour, cooled, and an N-octadecyl-1-hydroxy-Z-naphthoylamine. The equal volume of water added. The dye crystals coated emulsion showed a high red sensitivity, Which-separated out on standing were filtered off and developed to a blue-green image with a pand recrystallized from methyl alcohol.

Example VI tion, since it will be apparent to those skilled in the art, that the dyes may be incorporated into photographic emulsions by methods other than those described herein.

This application is a division of our co-pending application Serial No. 549,789 filed on even date.

While there have been pointed out above certain preferred embodiments of the invention, the same is not limited to the foregoing examples, illustrations, or to the specific details given therein, but is capable of variations and modifications 3,3-diethyl-5,6-cyclohexylidenedioxy-B,6'-dimethoxybenzothiocarbocyenine iodide (lg H5 I 5.4 gms. of 2-(p-acetanilido viny1)-5,6-cyclohexylidenedioxybenzthiazole ethiodide was mixed with 4.2 gms. of 2-methyl-5,G-dimethoxybenzthiazole ethyl-p-toluenesulfonate, cc. of pyridine and 4 cc. of triethylamine. The mixture was heated to reflux for one hour, cooled, and an equal amount of water added. The dye crystals which separated out on standing were filtered off and recrystallized from methyl alcohol.

Incorporated in a gelatino silver halide emulsion containing about 45% of silver halide, the dye sensitized to about 6800 A, with a maximum sensitivity at 6400 A.

Twenty-five milligrams of the sensitizing dye prepared as above, was added to a kilo of silver halide gelatin emulsion containing about 10% gelatin, 4-5% of silver halide, and 12 gms. of a-hYdlOXy naphthoic acid as the color former. The coated emulsion showed a high red sensitivity, and developed to a blue-green image with a p-phenylenediamine developer.

In the preparation of silver halide emulsions containing the sensitizing dyes of the present invention, the dyes may be dissolved in methyl or ethyl alcohol and a volume solution containing from 5 to 50 milligrams of the dye added to a liter of emulsion. While in general practice it may not be necessary to add the dye in larger amounts, generally, for satisfactory results, amounts usually rangin from 5 to milligrams are sufficient to obtain the maximum sensitizing effect. However, we do not wish to limit our invention to the quantities just indicated; the most suitable amount will in each case be found by a few comparative experiments. The dyes may be added to the emulsion in form of solutions. In actual practice, the dyes are applied to the emulsion during any stage of its production; however, they are preferably added to the finished emulsion before being cast.

The above examples are illustrative only, and should not be construed as limiting the inven- N l C as to the reactants, proportions and conditions employed. Accordingly, it is intended that the invention be defined only by the accompanying claims, in which it is intended to include all features of patentable novelty residing therein.

We claim:

1. Compounds of the general formula:

R; x wherein R represents the methylene groups necessary to complete at least a 5-membered alicyclic ring system, R1 and R2 represent an alkyl group, X represents an acid radical, Y represents a member taken from the class consisting of sulfur and selenium, and Z represents the atoms necessary to complete a nitrogenous heterocyclic ring system of the type usual in cyanine dyes.

2. The c h e mi c a1 compound 3,3-diethyl- 5,6,5',6 dicyclohexylidenedioxybenzthiocarbocyanine iodide having the following formula:

CHa-CH 4. The chemical compound 3,3-diethyl-5,6- cyclo-hexylidenedioxy-5,6-dimethoxybenzothiocarbocyanine iodide having the following forring structure as part of the cyanine dye molemula: cule, which comprises reacting under the influ- C2415 \I 2 i 5. A process of preparin thio and seleno-carence of heat, one mol of 2-methyl-5,6-methylenebocyanine dyes containing a cyclic hydrocarbon dioxybenzselenazole ethyl ptoluenesulfonate substituted dioxy ring structure as part of the 15 with one mol of 2-(p-acetanilido vinyl) -5,6-,cycyanine dye molecule which comprises reacting clohexylidenedioxybenzthiazole ethiodide in the a member selected from the class of alicyclicdipresence of a basic condensing agent. oxybenzthiazoles and alicyclicdioxybenzselena- 8. A process of preparing a thio-carbocyanine zoles with a, member selected from the class concontaining a cyclopentylidenedioxy ring strucsisting of ethyl-orthoformate and a cyclammoture as part of the cyanine dye molecule, which nium quaternary salt, having an active group comprises reacting under the influence of heat, in the p-position and selected from the class conone mol of 2-methyl-5,6-cyclopenty i e o ysisting of alkyl mercapto and aryl acyl amino benzthiazole ethyl-p-toluenesulfonate with one groups under the influence of heat in the presmol of ethylorthoformate in the presence of a ence of a, basic condensing agent. basic condensing agent.

6. A process of preparing a thio-carbocyanine ALFRED W. ANISH. containing a cyclohexylldenedioxy ring structure LEE HENSLEY- as part of the cyanine dye molecules, which comprises reacting under the influence of heat, one REFERENCES CITED mol of 2-methyl-5,6-cyclohexylidenedioxybenz- The following references are of record in the thiazole ethyl-p-toluenesulfonate with one mol me of thi patent: of 2-(,B-acetanilido viny1)-5,6-methy1ened1oxybenzthiazole ethiodide in the presence of a basic UNITED STATES PATENTS condensing agent. Number Name Date '7. A process of preparing a thio-seleno car- 2,334,711 Kendall Nov. 23, 1943 bocyanine containing a cyclohexylidenedioxy 2,126,078 Zeh Aug. 9, 1938 

